package net.xdclass.utils;

import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.extern.slf4j.Slf4j;
import net.xdclass.model.MetaObjectWrapper;
import net.xdclass.model.MetaObjectsWrapper;
import org.apache.ibatis.reflection.MetaObject;
import org.apache.ibatis.reflection.SystemMetaObject;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.lang.reflect.Field;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.security.MessageDigest;
import java.util.*;
import java.util.function.BiFunction;
import java.util.function.Consumer;
import java.util.stream.Collectors;

@Slf4j
public class CommonUtils {
    /**
     * 获取ip
     * @param request
     * @return
     */
    public static String getIpAddr(HttpServletRequest request) {
        String ipAddress = null;
        try {
            ipAddress = request.getHeader("x-forwarded-for");
            if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getHeader("Proxy-Client-IP");
            }
            if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getHeader("WL-Proxy-Client-IP");
            }
            if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getRemoteAddr();
                if (ipAddress.equals("127.0.0.1")) {
                    // 根据网卡取本机配置的IP
                    InetAddress inet = null;
                    try {
                        inet = InetAddress.getLocalHost();
                    } catch (UnknownHostException e) {
                        e.printStackTrace();
                    }
                    ipAddress = inet.getHostAddress();
                }
            }
            // 对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
            if (ipAddress != null && ipAddress.length() > 15) {
                // "***.***.***.***".length()
                // = 15
                if (ipAddress.indexOf(",") > 0) {
                    ipAddress = ipAddress.substring(0, ipAddress.indexOf(","));
                }
            }
        } catch (Exception e) {
            ipAddress="";
        }
        return ipAddress;
    }



    public static String MD5(String data)  {
        try {
            java.security.MessageDigest md = MessageDigest.getInstance("MD5");
            byte[] array = md.digest(data.getBytes("UTF-8"));
            StringBuilder sb = new StringBuilder();
            for (byte item : array) {
                sb.append(Integer.toHexString((item & 0xFF) | 0x100).substring(1, 3));
            }
            return sb.toString().toUpperCase();
        } catch (Exception exception) {
        }
        return null;
    }

    /**
     * 獲取隨機數
     * @param length
     * @return
     */
    public static String getRandomCode(int length) {
        String source = "0123456789";
        StringBuilder sb = new StringBuilder();
        Random random = new Random();
        for (int i = 0; i < length; i++) {
            sb.append(source.charAt(random.nextInt(9)));
        }
        return sb.toString();
    }

    public static long getCurrentTimestamp() {
        return System.currentTimeMillis();
    }

    public static String getUUID() {
        return UUID.randomUUID().toString().replaceAll("-", "").substring(0, 32);
    }

    /**
     * 生成指定长度随机字母和数字
     *
     * @param length
     * @return
     */
    private static final String ALL_CHAR_NUM = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
    public static String getStringNumRandom(int length) {
        //生成随机数字和字母,
        Random random = new Random();
        StringBuilder saltString = new StringBuilder(length);
        for (int i = 1; i <= length; ++i) {
            saltString.append(ALL_CHAR_NUM.charAt(random.nextInt(ALL_CHAR_NUM.length())));
        }
        return saltString.toString();
    }

    public static void sendJsonMessage(HttpServletResponse response, JsonData jsonData) {
        ObjectMapper objectMapper = new ObjectMapper();
        response.setContentType("application/json;charset=utf-8");

        try (PrintWriter printWriter = response.getWriter()) {
            printWriter.print(objectMapper.writeValueAsString(jsonData));
            printWriter.flush();
        } catch (IOException e) {
            log.warn("響應給json數據給前端異常: {}", e);
        }
    }

    /**
     * 把對象封裝成MetaObject, 然后遍歷成員變量名稱做操作
     * @param object 要操作的對象
     * @param function 遍歷要調用的函數
     */
    public static void metaObjectHandle(Object object, Consumer<MetaObjectWrapper> function) {
        Field[] fields = object.getClass().getDeclaredFields();
        List<String> fieldNames = Arrays.stream(fields).map(item -> item.getName()).collect(Collectors.toList());

        MetaObject metaObject = SystemMetaObject.forObject(object);
        MetaObjectWrapper objectWrapper = new MetaObjectWrapper();
        objectWrapper.setMetaObject(metaObject);
        fieldNames.forEach(name -> {
            objectWrapper.setFieldName(name);
            function.accept(objectWrapper);
        });
    }

    public static void metaObjectsHandle(List<Object> objects, Consumer<MetaObjectsWrapper> function) {
        Map<String, MetaObject> metaMap = new HashMap<>(10);
        Set<String> fieldSet = new HashSet<>(10);
        objects.forEach(item -> {
            String className = item.getClass().getName();
            MetaObject metaObject = SystemMetaObject.forObject(item);

            // 只取類最后的名稱
            if (className.indexOf('.') != -1) {
                String[] names = className.split("\\.");
                metaMap.put(names[names.length - 1], metaObject);
            } else {
                metaMap.put(className, metaObject);
            }

            List<String>fieldNames = Arrays.stream(item.getClass().getDeclaredFields())
                    .map(field -> field.getName()).collect(Collectors.toList());

            fieldSet.addAll(fieldNames);
        });

        MetaObjectsWrapper objectsWrapper = new MetaObjectsWrapper();
        objectsWrapper.setMetaMap(metaMap);

        fieldSet.forEach(item -> {
            objectsWrapper.setFieldName(item);

            function.accept(objectsWrapper);
        });
    }
}
